handle incoming custom emoji reactions properly

app/lib/activitypub/activity.rb

@@ -181,24 +181,27 @@ class ActivityPub::Activity
 
   # Ensure all emojis declared in the activity's tags are
   # present in the database and downloaded to the local cache.
-  def process_emoji_tags
-    as_array(@object['tag']).each do |tag|
-      process_single_emoji(tag) if tag['type'] == 'Emoji'
+  # Required by EmojiReact and Like for emoji reactions.
+  def process_emoji_tags(tags)
+    as_array(tags).each do |tag|
+      process_single_emoji tag if tag['type'] == 'Emoji'
     end
   end
 
   def process_single_emoji(tag)
-    parser = ActivityPub::Parser::CustomEmojiParser.new(tag)
-    return if parser.shortcode.blank? || parser.image_remote_url.blank?
+    custom_emoji_parser = ActivityPub::Parser::CustomEmojiParser.new(tag)
+    return if custom_emoji_parser.shortcode.blank? || custom_emoji_parser.image_remote_url.blank?
 
-    emoji = CustomEmoji.find_by(shortcode: parser.shortcode, domain: @account.domain)
+    emoji = CustomEmoji.find_by(shortcode: custom_emoji_parser.shortcode, domain: @account.domain)
     return unless emoji.nil? ||
-                  parser.image_remote_url != emoji.image_remote_url ||
-                  (parser.updated_at && parser.updated_at >= emoji.updated_at)
+                  custom_emoji_parser.image_remote_url != emoji.image_remote_url ||
+                  (custom_emoji_parser.updated_at && custom_emoji_parser.updated_at >= emoji.updated_at)
 
     begin
-      emoji ||= CustomEmoji.new(domain: @account.domain, shortcode: parser.shortcode, uri: parser.uri)
-      emoji.image_remote_url = parser.image_remote_url
+      emoji ||= CustomEmoji.new(domain: @account.domain,
+                                shortcode: custom_emoji_parser.shortcode,
+                                uri: custom_emoji_parser.uri)
+      emoji.image_remote_url = custom_emoji_parser.image_remote_url
       emoji.save
     rescue Seahorse::Client::NetworkingError => e
       Rails.logger.warn "Error fetching emoji: #{e}"

app/lib/activitypub/activity/emoji_react.rb

@@ -9,14 +9,16 @@ class ActivityPub::Activity::EmojiReact < ActivityPub::Activity
               delete_arrived_first?(@json['id']) ||
               @account.reacted?(original_status, name)
 
+    custom_emoji = nil
     if name =~ /^:.*:$/
-      process_emoji_tags
+      process_emoji_tags(@json['tag'])
 
       name.delete! ':'
-      return if CustomEmoji.find_by(shortcode: name, domain: @account.domain).nil?
+      custom_emoji = CustomEmoji.find_by(shortcode: name, domain: @account.domain)
+      return if custom_emoji.nil?
     end
 
-    reaction = original_status.status_reactions.create!(account: @account, name: name)
+    reaction = original_status.status_reactions.create!(account: @account, name: name, custom_emoji: custom_emoji)
 
     LocalNotificationWorker.perform_async(original_status.account_id, reaction.id, 'StatusReaction', 'reaction')
   end

app/lib/activitypub/activity/like.rb

@@ -23,16 +23,16 @@ class ActivityPub::Activity::Like < ActivityPub::Activity
 
     custom_emoji = nil
     if name =~ /^:.*:$/
-      process_emoji_tags
+      process_emoji_tags(@json['tag'])
 
       name.delete! ':'
       custom_emoji = CustomEmoji.find_by(shortcode: name, domain: @account.domain)
       return false if custom_emoji.nil? # invalid custom emoji, treat it as a regular like
     end
-    return true if @account.reacted?(original_status, name, custom_emoji)
+    return true if @account.reacted?(original_status, name)
 
     reaction = original_status.status_reactions.create!(account: @account, name: name, custom_emoji: custom_emoji)
     LocalNotificationWorker.perform_async(original_status.account_id, reaction.id, 'StatusReaction', 'reaction')
-    return true
+    true
   end
 end

app/models/concerns/account_interactions.rb

@@ -243,8 +243,8 @@ module AccountInteractions
     status.proper.favourites.where(account: self).exists?
   end
 
-  def reacted?(status, name, custom_emoji = nil)
-    status.proper.status_reactions.where(account: self, name: name, custom_emoji: custom_emoji).exists?
+  def reacted?(status, name)
+    status.proper.status_reactions.where(account: self, name: name).exists?
   end
 
   def bookmarked?(status)

app/models/status_reaction.rb

@@ -24,6 +24,11 @@ class StatusReaction < ApplicationRecord
   private
 
   def set_custom_emoji
-    self.custom_emoji = CustomEmoji.local.find_by(disabled: false, shortcode: name) if name.present?
+    return if name.blank?
+    self.custom_emoji = if account.local?
+                          CustomEmoji.local.find_by(disabled: false, shortcode: name)
+                        else
+                          CustomEmoji.find_by(shortcode: name, domain: account.domain)
+                        end
   end
 end